Urinary Protein and Enzyme Excretion of Spot Urine in Children with Vesicoureteral Reflux

Yoon, Jung-Rim; Koo, Ja-Wook

doi:2009.13.1.56

J Korean Soc Pediatr Nephrol > Volume 13(1); 2009 > Article

J Korean Soc Pediatr Nephrol 2009;13(1): 56-62. doi: https://doi.org/10.3339/jkspn.2009.13.1.56

방광요관 역류증 환아의 단회뇨에서 요단백 및 효소 배설 측정

윤정림, 구자욱

¹인제대학교 의과대학 상계백병원 소아청소년과
²인제대학교 의과대학 상계백병원 소아청소년과

Urinary Protein and Enzyme Excretion of Spot Urine in Children with Vesicoureteral Reflux

Jung-Rim Yoon, Ja-Wook Koo

¹Department of Pediatrics, College of Medicine, Inje University, Sanggye Paik Hospital
²Department of Pediatrics, College of Medicine, Inje University, Sanggye Paik Hospital

ABSTRACT

Purpose : The aim of this study was to evaluate the clinical usefulness of measurement of ${beta}_2$ microglobulin (${beta}_2$ MG), N-acetyl-$beta$-D-glucosaminidase (NAG) of spot urine samples as indices of renal tubular damage and microalbumin of spot urine samples as a parameter of glomerular damage in children with vesicoureteral reflux (VUR) or renal defects.
Methods : We studied 91 children with previous UTI. The children were classified as 62 children without VUR and renal defects (group I), 10 children with VUR, without renal defects (group II), and 19 children with VUR and renal defects (group III). Patients having VUR were separated according to the degree of VUR (mild VUR: VUR grade I-III, severe VUR: VUR grade IV-V). Urinary excretion of ${beta}_$ microglobulin (${beta}_2$ MG), microalbumin, N-acetyl-$beta$-D-glucosaminidase (NAG), creatinine were measured in samples of morning urine specimens. Children with VUR or renal defects detected by voiding cystourethrography (VCUG) and DMSA renal scan were investigated.
Results : Microalbumin/Cr ratio of spot urine was significantly increased in group III compared group I ($42.3{pm}27.2;mg/gCr$ vs $25.2{pm}10.9;mg/gCr$, P<0.05). NAG/Cr ratio of spot urine was significantly increased in group II compared group I ($3.70{pm}23.4;mg/gCr$ vs $18.7{pm}12.7;mg/gCr$, P<0.05). There was no statistically significant difference of ${beta}_2$ MG/Cr ratio among three groups.
Conclusion : Urinary microalbumin excretion of morning urine sample may be a simple and reliable clinical indicators for early identification of renal damage in children with VUR and renal defects. Urinary microalbumin excretion may be useful marker to predict the the severity of VUR.

Key words: Microalbumin | N-acetyl-$\beta$-D-glucosaminidase (NAG) | ${\beta}2$ microglobulin (${\beta}2$ MG) | Vesicoureteral reflux (VUR)